I learned to fly with an Eaglet 50 back in the late 1980s. Liked that plane a lot, now I'm building two, one for my brother and one for myself. I would agree with Mike, go
with a .20 to .25. A .40 will require the engine mount to be moded, lead added to the tail and you will find that a bigger tank won't fit. A 6 oz tank is about the bigest tank
thatwill fit, the plans show a 4 oz tank.

Dave</p>